Trolling attachment for outboard motors

ABSTRACT

A trolling attachment for an outboard motor having a vertical column with an engine at the upper end thereof adapted to drive a horizontal screw at the lower end thereof, the boat being steerable by turning said column about a vertical axis, said attachment consisting of a crossarm fixable to or integral with said column, said crossarm carrying an electric motor at each end thereof each adapted to drive a small propeller, said propellers being disposed respectively at laterally opposite sides of the main screw, and means for operating said motors either separately or concurrently.

United States Patent [72] Inventor Manfred H. Guenther 610 E. 151st Terrace, Grandview, Mo. 64030 [21] Appl. No 801,691 [22) Filed Feb. 24, 1969 [45] Patented Aug. 3, 1971 [54] TROLLING ATTACHMENT FOR OUTBOARD MOTORS 3 Claims, 7 Drawing Figs.

[52] US. CL... 115/18A (51] Int. Cl B63h 21/26 [50] Field oi'Search 318/68, 80; 115/18 E, 18 A; 248/221 [56] References Cited UNITED STATES PATENTS 1,922,226 8/1933 Wilson et a1. 318/68 X 2,891,205 6/1959 Freeman 114/144 X 3,139,853 7/1964 McCarthy et a1. 115/18 3,199,815 8/1965 Martinkovic et a1 248/221 X FOREIGN PATENTS 1,074,445 7/1967 Great Britain 318/80 Primary Examiner Andrew H. Farrell Attorney-John A. Hamilton ABSTRACT: A trolling attachment for an outboard motor having a vertical column with an engine at the upper end thereof adapted to drive a horizontal screw at the lower end thereof, the boat being steerable by turning said column about a vertical axis, said attachment consisting of a crossarm fixable to or integral with said .column, said crossarm carrying an electric motor at each end thereof each adapted to drive a small propeller, said propellers being disposed respectively at laterally opposite sides of the main screw, and means for operating said motors either separately or concurrently.

PATENTEDMIG 3971 3,596,625

SHEET 1 OF 2 J2 Fig. 4

I N VEN'I T.) R

Manfred H. Gwyn/her BY flfforney.

PATENTEDAUB 3|97I 3,596,625

SHEET 2 OF 2 A liar/Jay.

TROLLING ATTACHMENT FOR OUTBOARD MOTORS This invention relates to new and useful improvements in trolling equipment for motor boats equipped with outboard motors.

In certain types of fishing from a boat, commonly known as trolling, it is desirable both that the boat move at an extremely slow speed and with a high degree of silence, in order not to alarm the fish. As is well known, it is very difficult to operate the usual outboard motor to drive the boat at speeds as slow as required for trolling, said motors commonly not being geared for these speeds, and said motors are also usually too noisy in operation for good trolling. Various types of auxiliary trolling motors, usually electrically driven, have heretofore been provided, but within my knowledge have been subject to certain disadvantages. They are generally separate from the primary outboard motor, and so require separate handling and transportation to and from the boat, and also separate mounting on the boat. This is tedious and laborious work for the fisherman. Also, since the primary outboard motor usually must be mounted in the ordinary manner to drive the boat to and from particular fishing areas, the auxiliary trolling motor usually must be mounted at one side of or otherwise offcenter from the midline of the boat, and this renders good steerage of the boat extremely difficult, particularly at low trolling speeds.

Accordingly, the principal object of the present invention is the provision of a trolling attachment which largely obviates the above enumerated disadvantages of preexisting devices, in that it may be permanently attached to, or formed unitarily with, an outboard motor of otherwise standard construction, so as to form a single unitary structure therewith for ease of handling and in that it provides efficient steerage at any speed.

Another object is the provision of a trolling attachment of the character described which provides for steering of the boat either in the usual manner, by turning the column of the outboard motor about a vertical axis, or by separate remote control means from any position in the boat. The latter provision permits the fisherman to fish from any desired position, and to steer the boat, without the undesirable noises caused by his moving to the usual position for steering at the stern.

Generally, the above objects are accomplished by the connection to the column of an outboard motor of an attachment including a pair of small, electrically driven trolling propellers disposed parallel with but respectively at laterally opposite side of the main screw of the outboard motor, and means for energizing said trolling propellers either one at a time or con currently, or at different speeds.

Other objects are simplicity and economy of construction, efficiency and dependability of operation, and adaptability of the attachment for connection to preexisting outboard motors of nearly any type.

With these objects in view, as well as other objects which will appear in the course of the specification, reference will be had to the accompanying drawing, wherein:

FIG. 1 is a fragmentary side elevational view of an outboard motor with a trolling attachment embodying the present invention mounted operatively thereon,

FIG. 2 is a rear elevational view of the parts as shown in FIG. 1,

FIG. 3 is a sectional view taken on line III-III of FIG. 2,

FIG. 4 is av schematic wiring diagram of the trolling attachment,

FIG. 5 is a view similar to FIG. 3, but showing a slightly modified construction,

FIG. 6 is an enlarged sectional view taken on line VI-VI of FIG. 5, and

FIG. 7 is a view similar to FIG. 4, showing a modification of the wiring diagram.

Like reference numerals apply to similar parts throughout the several views, and the numeral 2 applies to an outboard motor for boats, shown fragmentarily. Referring first to FIGS. l4, said outboard motor includes a vertical tubular column 4 through which extends a drive shaft 6. At the lower end of the column, said drive shaft operates suitable gearing, not

shown but well understood in the art, in a gearbox 8 forming a portion of the column, to drive a screw of propeller 10 the axis of which is horizontal. At the upper end of the column, not shown, drive shaft 6 is connected to and driven by a prime mover, generally a gasoline engine, mounted on the column, as is common in the art. It will be understood also that column 4 is commonly mounted on the stem or transom board of a boat by means permitting said column to be turned about a vertical axis parallel to shaft 6. Thus the boat may be steered, while screw 10 is operating to move the boat through the water, by turning column 2 to vary the angularity of the axis of screw 10 relative to the midline of the boat. A horizontal anticavitation plate 12 is attached to column 4 so as to overlie the zone of screw 10. This plate is disposed below the water level and has the usual function of preventing cavitation and vortexing of the water surface due to the action of the screw. All of the structure thus far described is of course common and well known in the art. 7

The trolling attachment forming the subject matter of the present invention includes a crossarm 14 attached at its midpoint to column 4 intermediate gearbox 8 and anticavitation plate 12, and extending horizontally in laterally opposite directions from said column. As shown, said crossarm, which is hollow, is provided at its rearward edge with a notch 16 which engages rearwardly about column 4 (see FIG. 3), and a U-bolt 18 bridges the rearward side of column 4, its legs extending forwardly through holes provided therefor in crossarm 14 and having nuts 20 threaded thereon forwardly of said crossarm. This permits the attachment to be added as auxiliary equipment to preexisting outboard motors of many different types. However, said crossarm could of course be formed integrally with column 4, if desired to furnish the attachment as original equipment.

To each end of crossarm 14 is mounted an electric motor 22 having a housing 24 which is preferably but not necessarily integral with the crossarm. The output shaft of each motor 22 has affixed thereto a small trolling propeller 26. The axes of said propellers are parallel to the axis of screw 10, but are spaced equally at respectively opposite side of said screw. Motor housings 24 must of course be suitably sealed against the entry of water therein. The orbits of propellers 26 must not interfere with the orbit of screw 10.

Motors 22 are furnished with electric power from a suitable source such as storage battery 28, with which many motor boats are already equipped. As shown, one terminal of said battery is connected by wires 30 and 32 to one terminal of each of said motors. The other terminal of battery 28 is connected by wires 34 and 36 with one pole of each of a pair manually operable, normally open switches 38 and 40. The opposite poles of said switches are connected respectively by wires 42 and 44 with terminals of the two motors. Wires 30, 40 and 42 are led to the motors from the battery, which is of course disposed in the boat, through a tubular conduit 46 extending above water level and secured at its lower end in crossarm 14 just ahead of column 4. The wires extend downwardly through said conduit, then outwardly through the hollow interior of said crossarm to motor housings 24. Switches 38 and 40 may be mounted in a suitable housing indicated schematically at 48. Housing 48 may be portable, lead wires 34, 42 and 44 to the switches being by means of a flexible cable, so that said switches may be carried about in the boat and operated from any position. The closure of switch 38 completes an operating circuit to the left motor 22 in FIG. 4, and the closure of switch 40 completes the operating circuit of the right motor.

In use, propellers 26 and their mounting and driving means are normally left in position at all times, so that there is no necessity for the fisherman to transport or install two separate assemblies, but only a single unitary structure. However, screw 10 and propellers 26 are not normally used simultaneously. Screw 10 is used in the usual manner to move the boat to a trolling location at any desired speed, the the prime mover driving said screw is deactivated, and motors 22 are activated by closure of switches 38 and 40 to drive the boat at the lower trolling speed. In this connection, motors 22 may be very small and have a very low power consumption. Also, they are quite silent as compared to the usual gasoline engine which drives screw 10.

The use of two trolling propellers, as shown, provides a novel convenience and selectivity of steering. Being disposed equal distances at laterally opposite sides of screw 10, they provide a composite thrust aligned with that of screw 10, so long as they operated at equal speeds. Thus the boat may be steered in the usual way by turning column 4 about a vertical axis relative to the boat. However, this type of steering requires the operator to remain at the stern of the boat to turn the outboard, which may be inconvenient as relates to fishing operations. The operator could fish from any part of the boat, and move to the stern whenever he desires to change course, but this is also convenient, and furthermore causes objectionable noises which could alarm the fish. With the attachment as shown column 4 of the outboard motor can be clamped in position to dispose the axes of screw 10 and propellers 26 parallel to the midline of the boat, and the boat hereafter steered by selective operation of one motor 22 or the other. Operation of left motor 22 without the right motor turns the boat to the right, and vice versa. As long as switches 38 and 40 are carried in a portable housing 48 with its electrical leads enclosed in a flexible cable, this type of steering can be performed from any position in the boat.

Referring next to FIGS. and 6, showing a modification of the structure, it will be seen that motor housings 24 are not fixed relative to crossarm 14 as in FIGS. 1-3, but that each motor housing is pivotal relative to said crossarm about a vertical axis, each motor housing being provided with an ear 50 secured in the crossarm by a vertical pivot bolt 52 having a wing nut 54 which when tightened secures the associated housing against pivotal movement. With this arrangement, it may be preferable that the electrical lead wires to the motors be contained in waterproof conduits 55 extending from tube 46 to said motors. By loosening said bolts, the motor housings may be adjusted to any position between a position in which the axes of propellers 26 are parallel with the axis of screw 10, as in FIGS. 1-3, to a position in which the axes of the propellers are widely divergent to the rear, as shown in FIGS. This divergent relationship assists in the steering action of propellers 26 as already described. When both of propellers 26 as in FIG. 5 are turned at the same speed, they still drive the boat straight in a forward direction as before but when one propeller is shut 05, the left in operation has a greater thrust laterally of the boat, and therefore has a stronger tendency to change the course of the boat, than it would if its axis were parallel to that of screw 10. This modification is particularly important in view of the usual extremely low power, low thrust characteristics of propellers 26.

The modification of the motor control system as shown in FIG. 7 also relates to easier, more efficient steering by means of propellers 26. This control systems is the same as that shown in FIG. 4, except that in place of the two simple on-off switches 38 and 40 carried in control box 48, there are substituted a pair of variable resistance devices each having an armature 56 movable over a conductor member having a resistive portion 58 and a nonresistive portion 60. Wires 34 and 36 are connected to armatures 56 while wires 40 and 42 are connected respectively to each of the conductor members at the juncture 62 of the resistive and nonresistive portions thereof. Armatures 56 are fixed on a single shaft 64 which may be turned by a knob 66 external to box 48. When armatures 56 are disposed at junctures 62, both of motors 22 receive full battery voltage. When shaft 64 is turned in one direction, one of armatures 56 moves onto a resistor 58, showing the motor associated therewith, while the other armature moves onto a nonresistor 60 whereby the motor associated therewith is allowed to maintain full speed, and vice'versa. Thus the degree of turning of the boat may be adjusted by the degree to which knob 66 is turned, for example to cause that boat to circle continuously about a relatively large or small radius. The control system of FIG. 7 may of course be used either in the species of FIGS. 1-3 or in the species of FIGS. 5-6.

While I have shown and described specific embodiments of my invention, it will be readily apparent that many minor changes of structure and operation could be made within the scope of the invention as defined by the appended claims.

What I claim as new and desire to protect by Letters Patent 1s:

1. In combination with an outboard motor having a vertical column adapted to be mounted on a boat for rotation on a vertical axis a screw carried for rotation on a horizontal axis at the lower end of said column, and a prime mover carried at the upper end of said column for drivingisaid screw, trolling means comprising:

a. a pair of electric motors,

b. means mounting said motors on said column,

c. a trolling propellar mounted on and driven by each of said motors, the axes of said propellers being horizontally offset from but disposed in lateral symmetry with respect to the vertical plane of the axis of said screw and being angled horizontally with respect to the axis of said screw in equal degree but in opposite directions, and

d. an operative electrical circuit for each of said motors, said circuit including a source of electric power and a switch, whereby said motors may be operated selectively either simultaneously on separately.

2. The combination as recited in claim 1 wherein each of said motors is mounted on said column by means permitting pivoting thereof about a vertical axis, whereby the axes of said trolling propellers may be disposed either parallel to the axis of said screw or horizontally angled with respect thereto in equal degree but opposite directions.

3. The combination as recited in claim 1 wherein each of said motor circuits includes a variable resistor operable when in the circuit to variably reduce the speed of said motor, anda 3 single control handle manually operable to control both of said resistors, said control handle leaving a neutral position in which neither of said resistors is connected in its associated motor circuit, but being operable by movement thereof in respectively opposite directions from said neutral position to insert one or the other of said resistors into its associated motor circuit, and to regulate said resistance. 

1. In combination with an outboard motor having a vertical column adapted to be mounted on a boat for rotation on a vertical axis a screw carried for rotation on a horizontal axis at the lower end of said column, and a prime mover carried at the upper end of said column for driving said screw, trolling means comprising: a. a pair of electric motors, b. means mounting said motors on said column, c. a trolling propellar mounted on and driven by each of said motors, the axes of said propellers being horizontally offset from but disposed in lateral symmetry with respect to the vertical plane of the axis of said screw and being angled horizontally with respect to the axis of said screw in equal degree but in opposite directions, and d. an operative electrical circuit for each of said motors, said circuit including a source of electric power and a switch, whereby said motors may be operated selectively either simultaneously on separately.
 2. The combination as recited in claim 1 wherein each of said motors is mounted on said column by means permitting pivoting thereof about a vertical axis, whereby the axes of said trolling propellers may be disposed either parallel to the axis of said screw or horizontally angled with respect thereto in equal degree but opposite directions.
 3. The combination as recited in claim 1 wherein each of said motor circuits includes a variable resistor operable when in the circuit to variably reduce the speed of said motor, and a single control handle manually operable to control both of said resistors, said control handle leaving a neutral position in which neIther of said resistors is connected in its associated motor circuit, but being operable by movement thereof in respectively opposite directions from said neutral position to insert one or the other of said resistors into its associated motor circuit, and to regulate said resistance. 